The present invention relates to a new and improved motor and motor control circuitry and more specifically to a nutating motor having a plurality of motor coils and control circuitry for controlling energization of the motor coils.
A known nutating motor is disclosed in U.S. Pat. No. 4,330,725 issued May 18, 1982 and entitled "Nutating Motor Coupling". The nutating motor disclosed in this patent includes a plurality of motor coils disposed on a stator having an upwardly facing annular array of gear teeth. A rotor is fixedly connected with a motor output shaft and has a downwardly facing annular array of gear teeth. Upon sequential energization of the motor coils, the rotor is tilted relative to the stator to move the annular arrays of gear teeth into meshing engagement. Sequential energization of the motor coils causes the rotor to nutate relative to the stator. As the rotor nutates relative to the stator, the annular arrays of gear teeth cooperate to effect relative rotation between the rotor and the stator.
Control circuitry for a nutating motor is disclosed in U.S. Pat. No. 4,303,871 issued Dec. 1, 1981 and entitled "Nutating Motor Current Control". The control circuitry disclosed in this patent includes switches or Darlington amplifiers which are connected with opposite ends of motor coils. By sequentially operating the switches from a nonconducting condition to a conducting condition, the motor coils are sequentially energized to effect nutational and rotational movement of the rotor relative to the stator. The switches for any one of the motor coils are simultaneously operated from a nonconducting condition to a conducting condition to effect energization of the one motor coil and are subsequently simultaneously operated from the conducting condition to a nonconducting condition to effect de-energization of the one motor coil. As the one motor coil is de-energized, energy from the one motor coil is utilized to energize another motor coil.
Nutating motors have previously been utilized to operate many different devices including valves. One way of connecting a nutating motor with a valve is disclosed in U.S. Pat. No. 4,360,752 issued Nov. 23, 1982 and entitled "Nutating Motor Gate Valve Operator and Rotor Assembly". Another way of connecting a nutating motor with a valve is disclosed in U.S. Pat. No. 4,436,278 issued Mar. 13, 1984 and entitled "Disconnectable Valve Motor Drive".